Tapered reamer



May 12, 1970 J. P. STEINDLER IAPERED REAMER Filed Aug. 21, 1967 UnitedStates Patent 3,510,990 TAPERED REAMER Julius P. Steindler, Chicago,Ill., assignor to Engis Equipment Company, Morton Grove, Ill., acorporation of Illinois Filed Aug. 21, 1967, Ser. No. 662,122 Int. Cl.B24d 5/10 U.S. Cl. 51-206 2 Claims ABSTRACT OF THE DISCLOSURE A taperedreamer partially coated with abrasive particles grouped to form on anouter conical working surface of the reamer spatially isolated islandsconstituting separate grinding zones, the islands being distributedcircumferentially about the body of the reamer and overlapping axiallytherealong to provide an improved grinding and shaping tool.

This invention relates to an abrasive tool for grinding and shaping awall surface of a workpiece. More particularly, the invention isdirected to a diamond coated tool having a convex, generally conicalcutting and abrading surface for dressing a surface bounding a preformedconical hole in a workpiece of glass or physically related vitreousmaterial. The tool of the invention finds specific utility in theshaping and finishing of sockets of stopcock assemblies so that thesesockets conform precisely to peripheral wall contours of cooperatingplug elements of such assemblies to establish smooth and uninterruptedsubstantially sealing contact along mating contiguous surfaces thereof.

Many and varied diamond coated abrasive tools are known in the priorart, and some of these tools have been proposed specifically for thesame applications in which the tools of the instant invention are used.However, each of these prior art tools has important deficiencies orshort comings which have impaired their usefulness and prevented theirgeneral acceptance and utilization for the purposes intended. Forexample, some of the tools have been fabricated with their taperedsurfaces covered completely with abradant, unduly increasing rotationaltorque requirements in the grinding operation. Others have utilizedabrasive strip or zone formations which have tended to effect an axialdrawing in of the tool during use thereof. Still others have relied uponunduly complex forms or patterns, such as continuous spiral helicies,for the abradant material. It is the aim of the present invention toprovide diamond coated tapered grinding tools which obivate thedeficiencies and inadequacies of prior art devices.

Considered broadly, the tapered abrasive tools of the invention include,in each case, a conical surface having embedded therein grouped abradantparticles, the groups being spaced from one another to define islands orzones of abrasive material distributed over the tool surface. Thetool-carried islands overlap axially so that for each rotation of thetool in the workpiece, the entire conical surface of the workpiece istraversed by abrasive material so that objectionable grooving or scoringof the workpiece surface is obviated.

The nature and advantages of the invention will appear more fully fromthe following description and the accompanying drawing wherein preferredforms of the invention are shown. It should be understood, however, thatthe description and drawing are illustrative only and are not intendedto limit the invention except insofar as it is limited by the claims.

In the drawing:

FIG. 21 is a side elevational view of a reamer em- 3,510,990 PatentedMay 12, 1970 "ice bodying the features of the invention and depictingone geometric form of the abrasive zones;

FIG. 1A is a cross-sectional view taken on the line 1A1A of FIG. 1;

FIGS. 2 through 8 are views similar to FIG. 1 but showing other suitablegeometric configurations of the abrasive zones; and

FIG. 9 is a view, partly in vertical section, and showing a longitudinalbore and communicating radial ducts comprising conduit means forconveying lubricating and cooling fluid to the working areas of thetapered reamer.

Referring more particularly to the drawing, there is shown in FIG. 1 agrinding tool 20 including a tapered body 24, and an integrally formedcoaxial shank or shaft 26 by means of which the tool is held androtationally driven in use. Distributed over the conical surface 30 ofthe tool are spaced islands or zones 32 of abrasive particles 36,preferably diamond grit. While any preferred technique and means may-beused to bond or to affix the diamond particles 36 to the body 24 of thetool, in the illustrative example provided, the diamonds are electrometallically deposited utilizing a well known plating technique. Such atechnique is described in Seligman et al. U.S. Pat. No. 2,360,798.

In preferred embodiments of the invention, as shown in FIGS. 1A and 9,the tapered tool 20 is provided with an internal longitudinallyextending passage 40 communicating with generally radially disposedducts 44 having ports 46 opening at the tool surface 30 at positionsintermediate the abrasive islands. The internal conduits serve as meansfor conveying fluid to and from the working zones 32 to cool andlubricate the workpiece (not shown) and the tool 20 and to eifectremoval of abraded material from the regions being ground.

In accordance with the practice of the invention, the abrasive-surfacedislands may take any preferred, regular or irregular, shape or contour.They may be arranged in any desired formalized pattern or may bedistributed in a random array, provided, however, that in allarrangements there is provided axial overlapping of cutting zones sothat lengthwise continuity of abrasive material distributedlongitudinally along the conical surface of the tapered tool is assured.In FIGS. 1, 2, and 3 the abrasive islands 32, 32a and 32b take thegeneral shape of parallelograms, and in FIGS. 4, 5 and 7, trapezoids32c, 32d, and 32 Staggered rows of modified parallelograms 32g eachincluding a pair of opposed arcuate sides are shown in FIG. 8, circularislands 32h in FIG. 9, and oval-shaped islands 32c in FIG. 6.

It will be evident upon consideration of the present disclosure thatmany other island shapes and distribution may be used. Arrays such asthose illustrated in FIGS. 5 through 9 have the advantage of permittingeither clockwise or counterclockwise rotational tool drive since inneither alternative mode of operation will there be any propensity ofthe tool to be drawn into the hole in the workpiece or to bind. In allforms of the invention the multi-path continuous radial recess formed atareas of the tool which separate the islands ensure free, substantiallyunrestricted flow of cooling and lubricating fluid, whereby the fluid isreadily discharged from the grinding zones and ultimately recirculatedduring grinding operations.

While preferred constructional features and spatial arrangements of theabrasive islands of the invention are embodied in the illustrativeembodiments depicted herein, it is to be understood that changes andvariations may be made by those skilled in the art without departingfrom the spirit and scope of the appending claims.

What is claimed is:

1. In a tapered reamer for shaping a generally mating preformed openingin a workpiece and for dressing a laterally disposed conical wallsurface bounding said opening, said reamer including a rigid andessentially incompressible body portion having a taper anglesubstantially the same as a taper of said opening in said workpiece,said body portion being of circular cross-section and defining along itslongitudinally extending radial periphery a conical workpiece-engagingwall having embedded firmly therein to project radially outwardlythereof abradant particles for dressing said conical Wall surfacebounding said opening in said workpiece to shape said surface of saidconical wall of said workpiece to an ultimate configurationcorresponding to a peripheral contour correlated with a conical surfacedefined by said abradant particles of said reamer disposedlongitudinally along a working surface of said reamer at radiallyoutward limits thereof;

the improvement wherein said abradant particles are grouped to define aplurality of multi-particle hardsurfaced, unyielding islands distributedcircumferentially of said body portion of said reamer and longitudinallyalong said workpiece-engaging wall thereof;

said islands comprising discontinuous, mutually isolated physicallyfixed abrading zones of said tool, said zones being circumferentiallyspaced and overlapping axially to define an array such that any planepassing through said tool normally of a rotational axis 5 thereofintersects at least one of said zones.

2. The structure as set forth in claim 1 wherein said abradant particlesare diamond particles.

References Cited 10 UNITED STATES PATENTS 449,217 3/1891 Good 51206959,262 5/ 1910 Rees. 2,383,464 8/1945 Bown 51206 15 3,229,427 1/1966Goodhew 512 41 OTH ELL M. SIMPSON, Primary Examiner US. Cl. X.R.

